After upgrading to xCode 9 and OSX 10.13 I get this error:
/Users/rickschlueter/Dropbox/Goods Project/eBetsy/Salvage/Base.lproj/Main.storyboard: Exception while running ibtool: Placeholder for identifier 'UpstreamPlaceholder-ApW-3f-WBN' was set to '<IBNSNibExternalObjectPlaceholder: 0x7fee0b696dd0 identifier=UpstreamPlaceholder-zXL-lY-4qu>', but the object was deallocated. Is it missing a strong reference in the storyboard/nib?
the same storyboard compiles fine on my other Mac running xCode 9.0 and OSx 10.12.6
Until this is resolved, I'm dead in the water on my main dev machine.
